1. Field of the Invention
The present invention relates to a process for obtaining, from mammalian macrophages, a therapeutic product, active, notably, with respect to human tumor cells, and to the therapeutic product thus obtained.
As is known, the macrophages are, either tissular histiocytes, or circulating monocytes, movable cells in the reticulo-endothelial system. They are cells of large size, 15 to 30 microns, having a nucleus with a regular structure and a weakly basophilic cytoplasm. These cells have a great tendency to macrophagia and act either by direct macrophagia, for example on bacteria, or by contact cytotoxicity, in the absence of complement.
2. Description of the Prior Art
Research investigations have established that, under certain conditions, macrophages taken from animals, in particular from rodents, exert a cytotoxic effect on tumor cells of animal origin (for example, the researches of Evans and Alexander, Nature, 236, 1972, pp. 169-171 and R. Keller, J. of Exp. Med. Vol. 138, 1973, pp. 625-644). According to the prior researches, the macrophages exert their destructive action on tumor cells either by themselves, or through their supernatant liquids (J. Galderon, R. T. Williams and E. R. Unanue, Proc. Nat. Acad. Sci. USA., Vol. 71, No 11, pp. 4273-4277, November 1974), after having been activated in vivo, that is to say, taken from animals which have previously received an injection of inflammatory agents.
All this research has the common drawback of providing experimental systems which make use of macrophages kept alive, that is to say these researches describe results obtained by means of a temporarily existing system and, if such research has established scientific results, it does not however enable a product endowed with therapeutic activity to be obtained, the raw material applied being devoid of permanence.